White fluorescing marking inks for



United States Patent WHITE FLUORESCING MARKING INKS FOR TEXTILE IDENTIFICATION Edward A. McCaiferty, Cincinnati, Ohio, assignor to The National Marking Machine Company, Cincinnati, Ohio, a corporation of Ohio No Drawing. Application January 30, 1952, Serial No. 269,119

3 Claims. (Cl. 252-3012) This invention relates to white fluorescent dyestuffs and textile marking inks made therefrom which are normally colorless when viewed under normal light but fluoresce white when viewed under ultra violet light, and it particularly pertains to laundry marking inks composed of one or more of said white fluorescent dyestuffs dissolved in a carrying vehicle suitable for application of said ink to the textile material by any suitable mechanical markcolor or appearance of such fluorescent dyed textile ma- V terials under ordinary light is not important. Then, too, optical bleaches have been applied to white textile materials to whiten them and eliminate an off-white or yellowish tint. Dyestuffs for this purpose have sometimes been referred to as white dyes or dyestuffs, but this is some what of a misnomer since such reference is to the effect produced on the white textile materials rather than to the fluorescent color of the dyes or dyestuffs. The fluorescent color of the dyestuffs used for this purpose is not white but colored, their usual fluorescent color being blue, and, therefore, properly referred to as a blue fluorescent compound (Patent No. 2,528,323) or a colored or non-white fluorescent compound.

Fabric articles to be laundered, or some of the yarns or fibers thereof, may have been optically bleached and with different fluorescent colors. Obviously, it would be a most cumbersome and burdensome task if each article to be laundered had to be first subjected to an ultra violet light to determine whether or not it had been optically bleached to identify its fluorescent color, if optically bleached, and then be marked with a normally colorless marking ink having a fluorescent color contrasting with the fluorescent color of the article. Moreover, in ,addition to this inspection for determining the fluorescent color or colors of the articles to be laundered, many marking inks of difierent fluorescent colors would need to be used for marking the different fluorescent colored fabrics with the suitable contrasting one. Obviously a fluorescent ink of a character that would be suitable for marking all fabric articles, whether they are optically bleached or not, would be most desirable, yet the production of such a normally colorless dyestufi has not been heretofore attained.

Optical dyestuflf bleaches are normally colorless and invisible when applied to a textile. While normally colorless and invisible on the textiles, they fluoresce with a blue to violet coloration when exposed to ultra violet rays. White textile'fabrics when so bleached normally appear whiter. Blue fluorescent bleaches counteract the natural yellowishness or off-white color tint and increase the brilliancy of the fabric. Such bleaches are commonly used by commercial laundries and by original textile "ice manufacturers to improve the white appearance of the white textile fabrics and the pastel colorsunder natural light. The bleaches are separate preparations or may be included in the soap or cleaning agents. Accordingly, the vast majority of white and pastel colored fabrics are highly fluorescent when viewed under ultra violet light, but, without exception, all such bleaches fluoresce in various shades of blue to violet, and they are intended to do so.

Whether or not the fabrics are originally optically bleached, they may be subsequently bleached in a laundering operation, and, if the previous original bleaching dyestuffs or subsequently applied ones are not removed, there may well be several fluorescent colors in any one or more of the fabrics. It is also a fact that all of the fluorescent dyestuffs heretofore used in normally colorless marking inks also fluoresce in shades of blue to violet. Therefore, if any optically bleached textile fabric is marked with a normally colorless blue fluorescent dyestuif, it is not visible under an ultra violet light because its fluorescent spectrum is enveloped or blended in the fluorescent spectrum of the optical bleach of the textile. It is obliterated by the fluorescent spectrum of the optical bleach. The problem is comparable to, and has its counterpart, by way of example, in the visible spectrum. A visible marking ink of the same color asthe fabric to be marked would not be visible and would likewise be obliterated because there is no color contrast between the fabricand the mark.

This problem has now been overcome by the present invention of a white fluorescent dyestutf for use in laundry marking inks. Accordingly, plain or non-optically bleached fabrics, as well as optically bleached ones, can be marked in accordance with my invention, and the marking, viewed under ultra violet light, will fluoresce in contrast with the fluorescent color or colors of the optically bleached textile fabric as well as in contrast with the natural colors of non-optically bleached textile. And it matters not that the fabrics to be marked have been repeatedly optically bleached.

There is, so far as I am aware, no white fluorescent dyestutf or marking ink, or one which fluoresces white when subjected to ultra violet light. Consequently none of this character has been available for the manufacturer of textile marking inks, such as are used for marking fabric articles to be laundered. I

Accordingly, one of the objects of the invention is the production of normally colorless dyestufl which fluoresces white under ultra violet light.

Another object of the invention is the production of an ink which is suitable for marking all textiles, white or colored, and irrespective of whether or not any or all of said textiles are optically bleached.

Another object of the invention is' the production of a normally colorless dyestufl, and marking ink composed thereof, which is indelible enough to withstand at least one laundering.

Another object of the invention is the production of a dyestuff derivative, and textile marking ink composed thereof, comprised of an aromatic molecular structure having groups disposedto impart a white fluorescence to the dyestulf.

Another object of the invention is the production of a dyestufi derivative, and textile marking ink composed thereof, comprised of an aromatic molecular structure having opposite terminal groups which impart a white fluorescence to the dyestufi.

Another object of the .invention is the production of fluorescence to the dyestulf.

Still another object of the invention is the produc 2,734,871 I a 1 3 g 4 .1

tion of an amino stilbenc dyestufi derivative, and textile fluoresces blue. Acyl chloride is reacted in an aqueous marking ink composed thereof, having aromatic and non: media with aryl amine, the base stilbene compound, in aliphatic acyl groups as the opposite terminals of the the presence of alkali to produce opposite terminal groups linear molecular structure. thereon of benzoyl or b-napthoyl.

Still another object of'theiinvention is -a stilbene dye- 5 The R, R of the opposite terminal groups benzoyl has stuff derivative having ltlie characteristic of .fluorescing the following structural formula: whiteunder ailtra violet light and beingan amino stilbenc 0 compound structurally extended in such a way as toimg part the characteristic of whiteifluorescence. 0

Further objects, and-objects relating to details of com- 0 positionand economies of operation, will readily appear The R, R of the oppositeterminal groups b naphthoyl, from the detailed description to :follow. has the following structural formula In one instance, I have accomplished the objects of 0 my :invention by the 'dyestu'fii and.marking ink composi l] lions set forth in the following specification. Myinvention is clearly defined-and pointed out in the appended claims. Dyestuffs constituting preferred embodiments of any invention, as well as marking inks formed thereof, are set forth in the specification, but it will be under- Typlfymg and representative of the mventlon the stood that these typify the invention generically, and m dyestufi exafnples as specific g mfi that the invention is not limited to the specific embodithese being the base Stllbene compound with. the imp? ment disclosed for typifying the invention. nals acylsrwps f forth b The invention, broadly described, comprises an amino Exampie N 15 the w r E m p-(@ 9)!- stilbene dyestuit derivative having a linear aromatic polym fl 3 0lzvonzoylamino) stilbene 2:2 d1- acyl extended molecule that causes the said dyestuff de sodium sulfonate having the structural formula:

I o o 0 0 0 OaNa I OaNa rivative'to fluoresce white. The terminal groups are typi- Example No. 2 is the compound 4:4'-Di-p-(1b-.naphlied generally bya'cyl groups which are aromatic and not thoylaininobenzoylaminobenzoylamino) stilbene 2:2- aliphatic, with or without the auxochrome groups indisodiurn sulfonate having the "following structural forcluded therein. Acyl groups, without the inclusion of mula:

o o 0 V o o (f ii-HNO -nNO-g-HNO-cmon. NH-h-QNH-b-O-N dome one;

the auxochrome groups, are preferred as the terminals The specific method for forming above Example 1 is of the molecule, but the invention, in its broadest 'as- 40 as follows with the parts and percentagesgiven by weight pect, is directed to any opposite terminal groups in the andithe temperaturecscale in centigrade. linear aromatic molecular extension which impart a Five :parts 4:4-di-p-aminobenzoylaminobenzoylaminov white fluorescence. Accordingly, the acyl.-groups as the stilbene-2:2-disodium sulfonate as a 5% glycerol ,SOllh opposite-end terminals of the stilbene dyestufi derivative tionris mixed with 2 parts bcnzoic anhydride as a 10% are representative of and typify any end terminal linear glycol ether (.e.,-g. ethyleneglycol monobutyl ether) solu-.

groups which impart the characteristic of a white fluotion. With vigorous stirring the mixture is heated to bee rescence and are normally colorless in the visible spectween 90 to 1.00". The mixture is held at this temper-. mm. The dyestutf is also indelible when applied to :texature range for /2 hour or until clarificationis observed. tiles as a marking ink. The resultant concentrated dye solution-upon cooling may Auxochrome groups, such as hydroxyl, amino, snlfo, be used-directlyinpreparing the ink. carboxy or the like, maybe'present on the terminal aro- This procedure'eliminates the bothersome :and. time matic rings, but, since they tend to decrease the intensity consuming separation and drying operations. If, how- Of fi s y Preferably are-Omitted altogether eventhe solid product .of the reaction is desired, 1 part from Said Y E P concentrated dye solution is diluted with 2 par-ts ice-water,

ink marking textile fabrics 9 andthe resultant precipitate is filtered free and dried. by dissolving the novel white fluorescent dyestuii 'sttlbene derivative in a suitable carrying vehicle commonly used for making colorless fluorescent inks as in U. S. Patent No. 2,267,758, which is referred to and incorporated here as a part of the present invention for a disclosure of suitable liquid vehicles for colorless fluorescent markfollows with the parts and'percentages'likewise given by weight and the temperature scalein centigrade.

Five parts 4:4'-di-p-aminobenzoylaminobenzoylamino; stilbeneQ iT-disodium sulfonate as a 5% glycerol soluing dyesmfis in laundry marking inks tion is mixed with 3 .parts b-napthoylchloride as a 1 0%v .More specifically. described, the novel .dyestutl' is a gly 3. hlf i i i m npb r h t). 9 derivative of the base stilbene compound 4z4 -di-p-arniu At 2 h m x u e E Q S Y $I. d nobenzoylaminobenzoylamino stilbene 2:2 disul- T1011; liifi fi mme (01' suitable 03 1 ionic acid, having the following structural formula: is added-and the mixture is heated for-solution. There- 0 o 0 0 R-HNO-HN-C -QJ-HN-C CH=OH NH-iiQNH- -G-NH- sonar 'om This base stilbene compound, and method of forming sultant concentrated dye solution upon CO -l ng may :be i is i los d y O o L ng on pag 2 f Di Z isused di ee y nprepar n e nkh :$O id;P 'F1 chenprodukte sder. "lfeerfarbenfahrikation, published: by. 'desired,. it-is-separated-asin ExampleNo.1.

Otto Spamer, Leipzig, Germany. This case compound In preparing a l-ink the desired amountofdyeatufigcqh The specific method for forming above "Example? is-a's.

6 bodying the invention is dissolved in a suitable solvent. hicle, said dyestufi compound having a white fluorescence The solvent is merely a liquid vehicle carrier for the dyeunder ultra-violet light and comprising 4:4'-Di-p-(benstufi and may be of the character as that now commonly zoylaminobenzoylaminobenzoylamino) stilbene 2:2- used for fluorescent marking inks for fabrics. Ordinarily, disodium sulfonate having the structural formula:

0 El) (I) 0 0 O Na OaNa the vehicle has a concentration of about five-tenths 0 2. Anink for textile identification consisting essentially (0.5%) percent dyestufi of the character described. of a liquid carrying vehicle, of a viscosity and drying rate One preferred formula for compounding the ink is as suitable for use in a marking device, and a normally infollows: visible dyestuif compound dissolved in the liquid vehicle, white fluorescent d tufl "Percent" 5 said dyestuif compound having a white fluorescence (glycerine parts" 40 under ultra-violet light and comprising 4:4'-Di-p-(b- Isopropyl alcohol do 15 naphthoylaminobenzoylaminobenzoylamino) stilbene- Ethylene glycol monobutyl ether do 45 2:2'-disodium sulfonate having the structural formula:

0 O O O O O tHN lHN tHMQaH=CH NHt NHJl NHl OaNa OzNB From the foregoing description and the specific ex- 3. An ink for textile identification having a liquid amples of dyestuffs and ink formed therefrom, it will be carrying vehicle, of a viscosity and drying rate suitable seen that I have produced a dyestuff derivative which 5 for use in a marking device, and a normally invisible dyefluoresces white, this being typified by the two examples. stufl compound dissolved in the liquid vehicle, said in- The opposite terminal acyl groups represent and typify visible dyestutf compound characterized by white fluoresany terminal groups which will lineally extend the dyecence under ultraviolet light and consisting of an arostuf't molecule and cause the dyestufi to fluoresce white. matic polyacyl derivative of diamino stilbene disulfonic I am aware that there may be various changes in deacid having the general structural formula J U U LAJQU M L SO;Na O Na tails of construction and composition of both the dyestutf where R is a member of the class consisting of and the ink without departing from the spirit of my in- O vention, and, therefore, I claim my invention broadly as g indicated by the appended claims.

Having thus described my invention, what I claim as new and useful and desire to secure by United States 40 and Letters Patent, is: 0 1. An ink for textile identification consisting essentially ll of a liquid carrying vehicle of a viscosity and drying rate suitable for use in a marking device, and a normally invisibe dyestutr compound dissolved in the liquid ve- References Cited in the file of this patent UNITED STATES PATENTS 656,759 Great Britain Aug. 29, 1951 

3. AN INK FOR TEXTILE IDENTIFICATIN HAVING A LIQUID CARRYING VEHICLE, OF A VISCOSITY AND DRYING RATE SUITABLE FOR USE IN A MARKING DEVICE, AND A NORMALLY INVISIBLE DYESTUFF COMPOUND DISSOLVED IN THE LIQUID VEHICLE, SAID INVISIBLE DYESTUFF COMPOUND CHARACTERIZED BY WHITE FLUORESCENCE UNDER ULTRAVIOLET LIGHT AND CONSISTING OF AN AROMATIC POLYACYL DERIVATIVE OF DIAMINO STILBENE DISULFONIC ACID HAVING THE GENERAL STRUCTURAL FORMULA 